There’s no time limit in England and Wales for the police to prosecute your abuser. The Courts frequently try men who are well past retirement age who have no previous convictions, and put them in prison for offences of child abuse, even though they are frail and elderly.
There has to be enough evidence, however, to bring before the Courts and prove beyond reasonable doubt that a crime was committed. The longer the passage of time, the more difficult it is to do so.
There are time limits, however, for civil claims for compensation, and it’s sometimes more difficult to bring a claim without a successful criminal prosecution and/or supportive evidence.